Oil production



Sept. 10, 1940. J. NILES 2,214,064

OIL PRODUCTION Filed Sept. 8, 1959 2 Sheets-Sheet 1 (E 25 i r g a F a '6 17w 9 5 Q77 2 new/07 2' rug Sept. 10, 1940- O J. A. NILES 2,214,064

OIL PRODUCTION Filed Sept. 8, 19:59 2 Sheets-Shed 2 Patented Sept. 10, 1940 011. PRODUCTION Joseph A. Niles, Tulsa, Okla, assignor to Stanolind Oil and Gas Company, Tulsa, Okla, a corporation of Delaware Application September 8, 1939, Serial N 0. 293,945

8 Claims.

This invention relates to means and methods in connection with a well pumping operation for separating oil and water within the well and returning the water to the'formation from which it was derived or another formation without raising it to the surface of the well.

In oil well operation large quantities of water are frequently produced along with the oil. This is particularly true during the latter stages of the producing life of anoil well. Handling this water represents a great expense in lifting, separation'and disposed.

It is an object of my invention to eliminate the necessity for lifting, separating and disposing of this water. Another object of my invention is to provide an improved oil Well pumping system which will eliminate the production of water. It is also an object of my invention to provide a well pumping system in which the pressure in the sub-surface formation or formations is maintained by the immediate reinjection of any water which maybe produced. Other and more detailed objects, advantages and uses of my invention will become apparent as the description thereof pro-- ceeds.

When operating in accordance with my invention the water produced along with the oil is separated within the well, preferably near the bottom ofthe well and is returned to the oil producing sand or to another sand thus eliminating lifting and surface handling. The means and methods for accomplishing this will be described in detail in connection with the accompanying drawings which form a part of this specification and are to be read in conjunction therewith. These drawings are simplified diagrammatic sections of preferred embodiments of my invention and show in Figures 1 and 2, respectively, vertical sections of two alternative forms of apparatus for pumping and separating oil and water at the bottom of an oil well.

Turning first. to Figure 1, a bore hole I l is first drilled deeply into the sand l2 or other producing formation below the existing water level. Casing 45 I3 or blank liner is then run to the bottom of the hole cemented and perforated at two levels I 4 and I5, one at the top of the other at the bottom of this sand.

The pumping assembly shown in the drawings is then run in the hole. This assembly includes a packer I 6 which is shown in highly diagrammatic fashion and which is set between the perforations l4 and the perforations l5.

Above this packer is a conventional pump actuated by pump rods IT. -,This plunger and worksand l2 and the ing barrel includes the barrel l8, the standing valve l9 and the working valve 20. The working barrel is extended above its conventional lower end to form an elongated section 2| containing a spiral rib 22 running'around the inside of the 5 upper end of the barrel and forming a passage- .way to subject the well fluids to centrifugal force.

Further above the lower pump is located another pump which differs somewhat fromthe more conventional lower pump but is actuated 10 by the same pump rods IT. This upper pump includes standing valve 23 and working valve 24 within working barrel 25. It will be noted that this working barrel is of smaller cross section than the lower working barrel l8.

Around the outside of the pumps and preferably coincentric therewith area settling chamber 26 open at the top and a cha aiber 21 below the chamber 26. This lower chamber 21 is connected with tubing 28 which passes through packer I6 20 and communicates with the lower part of sand [2 through perforations I5. I

In the upper chamber 26 is an annular float 29 connected by rods 30 to a feather valve 3| which may be annular in form and which con- 25 trols the communication between chamber 26 and chamber 21.

The operation of the equipment just described isvas follows: The oil and water mixture enters the casing I 3 through the perforations l4 above 30 the packer l6 and is pumped upward by the lower pump which includes working valve 26. Before entering the upper chamber 26 it is preferably, but not necessarily, given a circular motion by the spiral fin 22 which tends to separate the oil and 35 water by centrifugal action.

Upper chamber 26 serves as a settling chamber and may be considerably more elongated than shown in the drawings. In this settling chamber further separation of oil and water occurs to 40 form an oil-water interface 32. The upper pump which includes Workingvalve 24 pumps the separated oil to the surface through tubing 33 inthe usual manner.

As soon as the fluid level reaches float 29 this 45 float is lifted and the feather valve 3| is thereby opened. This causes the water in the lower part of settling chamber 26 to flow by virtue of its hydraulic head into the lower annular chamber 21, and thence through tubing 28 and perforations l5 into the lower part of the producing formation l2.

The cross sectional areas of pumping barrels I 8 and 25 should be roughly in the ratio of the 55 arated water into the sand. This separated water entering the lower part of the sand mixes only very slightly with the incoming oil and water due to gravity separation which has been found to be quite effective, particularly if the sand is of considerable thickness.

If desired, still further improvement of the oil and water separation can be obtained by injecting any of the many known chemical demulsification agents into some part of the separation system. For instance, as shown in Figure 1, macaroni tubing 34 enters the upper part of the lower barrel in the vicinity of the lower end of spiral fin 22. A demulsifying agent injected through this macaroni tubing from the surface of the well serves to improve the oil and water separation, particularly if serious emulsification is encountered.

Turning now to Figure 2, it will be seen that this corresponds with Figure 1 in general and that corresponding parts are correspondingly numbered.

In Figure 2 instead of illustrating a. single sand or other producing formation, I have shown two sands l2a and I2!) which are separated by an impervious stratum 35. Thus, for instance, sand in and sand I2b can be separated by a shale lens 35 which is located approximately at the position of packer l6 so that perforations 14 are located opposite upper sand l2a while perforations I5 are located opposite lower sand 12b. The apparatus of Figure 2 also differs somewhat from that of Figure 1 and it will be apparent that either type of apparatus can be used either with a single sand or with two wholly or partially segregated sands.

In Figure 2 the float 29 together with the associated rods 30 and valve member 3| has an average specific gravity higher than that of oil but lower than that of water so that the float is maintained at the interface 32. Also in Figure 2 instead of having chamber 26 open at the top, it is closed by replacing the spider 36 of Figure 1 with the cylinder head 31 of Figure 2.

These changes involve some change in the operation of the system and give results which are in general preferable to those given by the device of Figure 1.

Using the apparatus of Figure 2, if no water is produced from the upper formation I211 the valve 3| remains closed and all production is delivered to the surface.

On the other hand, if a moderate amount of water is produced and the lower formation In is able to absorb it the operation of the float 29 serves to deliver the separated water to the lower formation and the separated oil to the surface through tubing 33 as in the case of the apparatus of Figure l.

However, if more water is produced than the lower formation l2b will normally take, the valve 3| of Figure 2 is held open and a high pressure begins to build up on the lower formation but not on the upper one. This pressure is, of course, limited by the head of liquid in tubing 33 unless supplemented by some such means as a choke in the tubing or a loading on the working valve 24 of the upper pump. When this excessive water is produced, the lower formation is obliged to take more water by virtue of the high pressure. Any excess'of water above that which the formation can take is, of course, pumped to the surface.

The pressure in chamber 28 can be limited, if

desired, by a pressure release valve 33 in cylinder head 31.

While our invention has been described with reference to pumping wells and is particularly applicable thereto, it will be apparent that separators of this type can also be applied to flowing wells in some instances.

The drawings are, as has been mentioned, purely diagrammatic and it will be evident that the mechanical details can be varied considerably without departing from the spirit of the invention.

I claim:

. 1. A method of producing oil from a sub-surface formation containing both oil and water which comprises producing oil and water into a well, separating said oil and water within said well, injecting said separated water directly into a sub-surface formation and conveying said separated oil to the surface.

2. A method of producing oil from a sub-surface formation containing both oil and water which comprises separating said oil and said water near the bottom of said well, injecting the separated water directly into a sub-surface formation at a level below the level from which said oil and water entered said well and conveying said separated oil to the surface.

3. Apparatus for producing oil from a formation containing both oil and water which comprises a well, a packer in said well, said well being in fluid communication with a porous formation above said packer and in fluid communication with a porous formation below said packer, a separator, means for conveying oil and water entering said well above said packer to saidseparator and means associated with said separator for conveying the separated water through said packer and into said porous formation below said packer.

4. Apparatus for producing oil from a formation containing both oil and water comprising a well, a packer in said well, said well being perforate both above and below said packer opposite at least one porous formation, a pump located above said packer, a separator connected with said pump, a second pump for conveying oil from said separator to the surface and means for conveying water separated in said separator through said packer and thence, to the porous formation located below said packer.

5. A device for pumping oil and separating oil and water comprising a well, a packer in said well, said well being perforate both above and below said packer opposite at least one porous formation, a pump located within said well above 'said packer, a separator communicating with the outlet end of said pump, a second pump having an inlet in communication with the upper part of said separator for conveying separated oil to the surface, means associated with the lower end of said separator for conveying separated water through said packer and thence to the porous formation located below said packer, valve means for controlling the flow of said separated water and means for controlling the actuation of said valve means in accordance with a liquid level within said separator.

6. Apparatus for producing oil from a formation containing both oil and water comprising a well, a packer in said well, said well being perforate both above and below said packer opposite at least one porous formation, a pump located above said packer, means associated with the outthe porous formation located below said packer.

7. A device for pumping oil and separating oil and water comprising a well, a packer in said well, said well being perforate both above and below said packer opposite at least one porous formation, a pump located within said well above said packer, a separator communicating with the outlet end of said pump, a second pump having an inletin communication with the upper part of said separator for conveying separated oil to the surface, means associated with the lower end of said separator for conveying separated water M through said packer and thence to the porous formation located below said packer, valve means for controlling the flow of said separated water and means for controlling the actuation of said valve means in accordance with the oil-water interfacial level within said separator.

8. A device for pumping oil and separating oil and water comprising a well, a packer in said well, said well being perforate both above and below said packer opposite at least one porous formation, a pump located within said well above said packer, means associated with the outlet of said pump for applying centrifugal force to the oil and water handled by said pump, a separator associated with said means, a second pump having an inlet in communication with the upper part of said separator for conveying separated oil to the surface, means associated with the lower end of said separator for conveying separated water through said packer and thence to the porous formation located below said packer, valve means for controlling the flow of said separated water and means for controlling the actuation ofs'aid valve means in accordance with a liquid level 20 within said separator.

' JOSEPH A. NlLES.

DISCLAIMER 2,214,064.J0seph A. Niles, Tulsa, Okla. OIL PRODUCTION. Patent dated September 10, 1940. Disclaimer filed February 25, 1942, by the assignee, Stanolind Oil and Gas Company.

Hereby enters this disclaimer to claime 2, 3, and 4, in said specification.

[Oflicial Gazette March 24, 1942.1 

